From 4a3d7f642670446f977a6328f82ab6c2f5305aff Mon Sep 17 00:00:00 2001
From: "Eugene (jno) Dvurechenski" <jno@linux.vnet.ibm.com>
Date: Fri, 29 Aug 2014 11:01:39 +0200
Subject: [PATCH] pc-bios/s390-ccw Really big EAV ECKD DASD handling
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For EAV ECKD DASD, the cylinder count will have the magic value
0xfffeU. Therefore, use the block number to test for valid eckd
addresses instead.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
(cherry picked from commit f04db28b86654d1c7ff805b40eff27bba6b0f686)
Signed-off-by: Andreas Färber <afaerber@suse.de>
---
 pc-bios/s390-ccw/bootmap.c | 31 +++++++++++++++----------------
 pc-bios/s390-ccw/virtio.c  | 11 ++++++-----
 pc-bios/s390-ccw/virtio.h  |  2 +-
 3 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c
index e4352b16cd..d4c579c245 100644
--- a/pc-bios/s390-ccw/bootmap.c
+++ b/pc-bios/s390-ccw/bootmap.c
@@ -93,11 +93,23 @@ static inline void verify_boot_info(BootInfo *bip)
                "Bad block size in zIPL section of the 1st record.");
 }
 
-static bool eckd_valid_address(BootMapPointer *p)
+static block_number_t eckd_block_num(BootMapPointer *p)
 {
+    const uint64_t sectors = virtio_get_sectors();
+    const uint64_t heads = virtio_get_heads();
     const uint64_t cylinder = p->eckd.cylinder
                             + ((p->eckd.head & 0xfff0) << 12);
     const uint64_t head = p->eckd.head & 0x000f;
+    const block_number_t block = sectors * heads * cylinder
+                               + sectors * head
+                               + p->eckd.sector
+                               - 1; /* block nr starts with zero */
+    return block;
+}
+
+static bool eckd_valid_address(BootMapPointer *p)
+{
+    const uint64_t head = p->eckd.head & 0x000f;
 
     if (head >= virtio_get_heads()
         ||  p->eckd.sector > virtio_get_sectors()
@@ -105,27 +117,14 @@ static bool eckd_valid_address(BootMapPointer *p)
         return false;
     }
 
-    if (!virtio_guessed_disk_nature() && cylinder >= virtio_get_cylinders()) {
+    if (!virtio_guessed_disk_nature() &&
+        eckd_block_num(p) >= virtio_get_blocks()) {
         return false;
     }
 
     return true;
 }
 
-static block_number_t eckd_block_num(BootMapPointer *p)
-{
-    const uint64_t sectors = virtio_get_sectors();
-    const uint64_t heads = virtio_get_heads();
-    const uint64_t cylinder = p->eckd.cylinder
-                            + ((p->eckd.head & 0xfff0) << 12);
-    const uint64_t head = p->eckd.head & 0x000f;
-    const block_number_t block = sectors * heads * cylinder
-                               + sectors * head
-                               + p->eckd.sector
-                               - 1; /* block nr starts with zero */
-    return block;
-}
-
 static block_number_t load_eckd_segments(block_number_t blk, uint64_t *address)
 {
     block_number_t block_nr;
diff --git a/pc-bios/s390-ccw/virtio.c b/pc-bios/s390-ccw/virtio.c
index 6ed3dc9cc2..c0540d1cd4 100644
--- a/pc-bios/s390-ccw/virtio.c
+++ b/pc-bios/s390-ccw/virtio.c
@@ -340,11 +340,6 @@ int virtio_get_block_size(void)
     return blk_cfg.blk_size << blk_cfg.physical_block_exp;
 }
 
-uint16_t virtio_get_cylinders(void)
-{
-    return blk_cfg.geometry.cylinders;
-}
-
 uint8_t virtio_get_heads(void)
 {
     return blk_cfg.geometry.heads;
@@ -355,6 +350,12 @@ uint8_t virtio_get_sectors(void)
     return blk_cfg.geometry.sectors;
 }
 
+uint64_t virtio_get_blocks(void)
+{
+    return blk_cfg.capacity /
+           (virtio_get_block_size() / VIRTIO_SECTOR_SIZE);
+}
+
 void virtio_setup_block(struct subchannel_id schid)
 {
     struct vq_info_block info;
diff --git a/pc-bios/s390-ccw/virtio.h b/pc-bios/s390-ccw/virtio.h
index f1fb1b08fa..c23466b8db 100644
--- a/pc-bios/s390-ccw/virtio.h
+++ b/pc-bios/s390-ccw/virtio.h
@@ -192,9 +192,9 @@ extern bool virtio_disk_is_scsi(void);
 extern bool virtio_disk_is_eckd(void);
 extern bool virtio_ipl_disk_is_valid(void);
 extern int virtio_get_block_size(void);
-extern uint16_t virtio_get_cylinders(void);
 extern uint8_t virtio_get_heads(void);
 extern uint8_t virtio_get_sectors(void);
+extern uint64_t virtio_get_blocks(void);
 extern int virtio_read_many(ulong sector, void *load_addr, int sec_num);
 
 #define VIRTIO_SECTOR_SIZE 512
